iOS: clear Keychain data on uninstall

ios/zeus/AppDelegate.m

@@ -24,6 +24,31 @@ static void InitializeFlipper(UIApplication *application) {
 }
 #endif
 
+/**
+ Deletes all Keychain items accessible by this app if this is the first time the user launches the app
+ */
+static void ClearKeychainIfNecessary() {
+    // Checks whether or not this is the first time the app is run
+    if ([[NSUserDefaults standardUserDefaults] boolForKey:@"HAS_RUN_BEFORE"] == NO) {
+        // Set the appropriate value so we don't clear next time the app is launched
+        [[NSUserDefaults standardUserDefaults] setBool:YES forKey:@"HAS_RUN_BEFORE"];
+
+        NSArray *secItemClasses = @[
+            (__bridge id)kSecClassGenericPassword,
+            (__bridge id)kSecClassInternetPassword,
+            (__bridge id)kSecClassCertificate,
+            (__bridge id)kSecClassKey,
+            (__bridge id)kSecClassIdentity
+        ];
+
+        // Maps through all Keychain classes and deletes all items that match
+        for (id secItemClass in secItemClasses) {
+            NSDictionary *spec = @{(__bridge id)kSecClass: secItemClass};
+            SecItemDelete((__bridge CFDictionaryRef)spec);
+        }
+    }
+}
+
 @implementation AppDelegate
 
 - (BOOL)application:(UIApplication *)application
@@ -39,6 +64,9 @@ - (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(
   InitializeFlipper(application);
 #endif
 
+  // Add this line to call the above function
+  ClearKeychainIfNecessary();
+
   RCTBridge *bridge = [[RCTBridge alloc] initWithDelegate:self launchOptions:launchOptions];
   RCTRootView *rootView = [[RCTRootView alloc] initWithBridge:bridge
                                                    moduleName:@"zeus"